I've not done an HPE but I have re-installed a vinyl roof in my coupe.
There are a few things I've learnt from that.
1. The glue does not have to be ultra strong, its there to hold the material in place, the push fit edging is the bit that really holds it all in nice and tight. Carpet glue is all I used and its still held in place with no sagging etc.
2. Buy a big pack of medium sized plastic clothes pegs (These will be your friends) Alternatively nick them from your washing line. (My wife went just a little bit potty when she saw all her pegs holding my vinyl roof in place. They are like having 25 extra pairs of hands
They clamp just at the right strength without causing any distortion.
3. Take your time, glue shortish lengths at a time, if you have a sunroof then start from the sunroof aperture and work outwards.
4. Take your time! Do either front first back second or left first then right second. Don't work round in a circle!
5. Take your time! and don't be afraid of the task, it's not as daunting as you'd think.
6. Did I mention you should take your time over it?